分机号码

例句：

1. 1. The company has extended its reach to new markets.
   该公司已将其业务扩展到新的市场。
2. 2. The train's length is an extension of the track.
   火车的长度是轨道的延伸。
3. 3. The artist added a few more colors to her painting for the extension.
   艺术家在画作中添加了更多的颜色以增加长度。